Longitudinal evaluation of cartilage composition of matrix-associated autologous chondrocyte transplants with 3-T delayed gadolinium-enhanced MRI of cartilage.
OBJECTIVE
The purposes of this study were to use delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) to evaluate the zonal distribution of glycosaminoglycans (GAGs) in normal cartilage and repair tissue and to use 3-T MRI to monitor the GAG content in matrix-associated autologous chondrocyte transplants.


METHODS
Fifteen patients who underwent matrix-associated autologous chondrocyte transplantation in the knee joint underwent MRI at baseline and 3-T follow-up MRI 1 year later. Total and zonal changes in longitudinal relaxivity (deltaR1) and relative deltaR1 were calculated for repair tissue and normal hyaline cartilage and compared by use of analysis of variance.


RESULTS
There was a significant difference between the mean deltaR1 of repair tissue and that of reference cartilage at baseline and follow-up (p < 0.001). There was a significant increase in deltaR1 value and a decrease in GAG content from the deep layer to the superficial layer in the reference cartilage and almost no variation and significantly higher values for the repair tissue at both examinations. At 1-year follow-up imaging, there was a 22.7% decrease in deltaR1 value in the deep zone of the transplant.


CONCLUSIONS
T1 mapping with dGEMRIC at 3 T shows the zonal structure of normal hyaline cartilage, highly reduced zonal variations in repair tissue, and a tendency toward an increase in global and zonal GAG content 1 year after transplantation.
Pinker
Katja
K
Department of Radiology, MR Centre of Excellence, Medical University Vienna, Lazarettg. 14, 1090. Vienna, Austria.
Szomolanyi
Pavol
P
Welsch
Goetz C
GC
Mamisch
Tallal C
TC
Marlovits
Stefan
S
Stadlbauer
Andreas
A
Trattnig
Siegfried
S
D000328:Adult; D019902:Chondrocytes / Q000378:metabolism / Q000473:pathology / Q000637:transplantation*; D003287:Contrast Media; D005260:Female; D050724:Fractures, Cartilage / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery*; D019786:Gadolinium DTPA; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis* / Q000601:surgery*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D003287:Contrast Media; D006025:Glycosaminoglycans; D019786:Gadolinium DTPA